Aircraft have to be able to fly in safety without occurrence of a malfunction, an unforeseen behavior (up-set), or others in High Intensity Radiated Fields (HIRF), which represents an electro-magnetic environment from radio, television, radar, emitters, and other sources during cruising flight or during takeoff or landing. To this end, HIRF protection measures required in (14 CFR) sections 23.1308, 25.1317, 27.1317, and 29.1317 of High-intensity Radiated Fields (HIRF) protection, which stipulate regulations (airworthiness requirements) of Federal Aviation Administration (FAA), have to be taken.
The importance of protection of electric/electronic systems of aircraft has been significantly increasing in recent years for the following reasons:    1) a greater dependence on electric/electronic systems performing functions required for continued safe flight and landing of the aircraft;    2) a decrease in electromagnetic shielding by a composite material of some kind for use in designing aircraft;    3) an increase in susceptibility (sensitivity) to HIRF of electric/electronic systems accompanied by a higher speed of the operating speed of a data bus and a processor, a higher-density of an IC and a card, and a higher degree of sensitivity of electronic equipment;    4) an expansion of use frequency to a high-frequency band of, in particular, 1 GHz and higher;    5) an increase in severity of an HIRF environment with an increase in the number of RF transmitters and electric power; and    6) an adverse affect on part of aircraft when exposed to HIRF environment.
On the other hand, inside an aircraft, due to radio wave and electromagnetic noise (hereinafter simply referred to as electromagnetic noise) emitted from various electronic equipment, such as portable telephones, game machines, notebook-sized personal computers, and PEDs (Personal Electro Devices), such as an active-type RFID (Radio Frequency IDentification) tag attached to air freight cargo, an adverse effect can occur in, for example, communications with a control tower and communications and control of navigation for flight via a predetermined route. Thus, as well known, passengers are asked to refrain from using various electronic equipment inside aircraft.
Since the airframe of an aircraft is generally formed of metal, electromagnetic noise comes and goes from a cabin (a seat space) to a cockpit (a flight deck) and an avionics bay mainly through a cabin window and a cockpit window. Thus, in order to prevent electromagnetic noise that can be a hindrance from entering the cockpit and the avionics bay, a film made of ITO (Indium Tin Oxide), gold, silver, or the like is provided as being inserted to the cabin window made by laminating a plurality of window panels made of acrylic or the like (for example, refer to Patent Document 1).